Artificial yarn, particularly artificial silk yarn



July 12, 1932. A -z'AR"r TAL 1,867,298

ARTIFICIAL YARN, PARTICULARLY ART'IFIGIAL SILK YARN Filed De.- 3.5. 1928 ii-form a product of previously unknown qual Patented July 12, 1932 UNITED STATES PATENTV'OFFICE FRANZ nonnxnsmr, or BARMEN-RITTEBSHAUSEN, -memcm Bananas coaronn'rron, on NEW, YORK, is. Y.

GERMANY, ASSIGNQRS .TO

murmur. YARN, PARTICULARLY ARTIFICIAL SILK um Application filed December 18,1928, Serial No. 326,892, and in Germany May 5,1928.

This invention relates to an improvement in artificial yarns, particularly artificial silk yarns.

Artificial yarns, particularly artificial silk yarns, are composed of a large number of continuous individual filaments which are comparable to the fibres of ordinary yarns.

of natural silk yarn and retain the unity of the individual filaments. There is, however, in this connection a limit, and in fact it is determined by the resistance of the individual filaments, (the lower limit lies at about 1 denier per individual filament). If the individual filaments are too thin, they tear, and the yarn has, as the expression has it,

broken filaments. This breaking of the the spinning funnel.

filaments may take place either before or after stretching.

We have succeeded in producing an artificial yarn of increased resistance, and in fact, by subjecting the cellulose thread, after it has been brought to a certain stage, to a further stretching outside the precipitating bath. For example. with silk produced from cuprammonium cellulose solution, an increase in resistance of 100 per cent has been obtained by stretching the yarn while-still in the plastic condition outside the spinning funnel and after the stretching effected in The increase in resistance depends upon the degree of stretchmg.

It is possible according to the invention, with asilk having an increased resistance of this kind.'t0 reduce the individual filaments of the yarn below 1 denier for the individual filaments Without danger existing of breaks and the formation of broken filaments either before or after stretching, that is thus. to form cellulose silk yarn from individual filements of increased resistance and having a titer of less than 1 denier. With this, such a yarn presents the same soft lustre as nat ural silk. Yarns of this kind are new and deniers in the dry condition and 185 grams per 100 deniers in the'wet condition.

The accompanying drawing is an enlarged cross-section through a yarn according to our invention made from copper oxide ammonia cellulose solution by the stretch spinning process. Each individual filament has an essentially circular cross-section while the individual filaments of other artificial silk yarns have a flat, elongated, oval-shaped or kidney-shaped cross-section;

The denier is a measure of *the'fineness of the thread which is usual in the silk industry. The number of deniers is equalto the weight in grams of a thread of 9,000 meters in length. v

The formerly known yarns of artificial silk, the individual filaments of which possessed. a fineness below 1.5 deniers, had, at the most, a tear resistance of 170 to 185 grams in the dry condition, and to ams in the wet condition. Yarns with in ividual filaments, the titer of which lies under one denier, have not essentially been known. The yarns according to the invention, on the other hand, the individual filaments having titers of 1 denier and below, have a resistance of at least 220 grams per deniers in the dry condition, and grams per 100 deniers in the wet condition.

The resistance figures given were ascer tained with a thread humidity of 11 per cent for the dry condition, and in the completely wetted condition respectively at room temperature. For the tests, the so-called Schopper strength testing apparatus or serimeter was used for working on a free piece of yarn of 50 centimeters length. The speed of tearing amounted to 50 centimeters per lin'nute. 4

The titer of the yarn was likewise asccr tained with 11 per cent thread humidity.

v material is capable of be" The yarn produced in accordance with the invention has about double the resistance of the artificial silk which has been known I hitherto. Moreover, it has the same lustre as natural silk and attains to or exceeds this in relation to the feel and resistance, as the individual filaments are finer than those of natural silk. Owing to these properties, the

used to an increased extent for the production of textile products, andparticularly for 'such products which are to be washable.

What we claim is 1. Yarn 1 artificial origin comprising fila ments with an individual titre of less than 1 denier, said yarn having a dry strength; of at least 2.2 grams per denier and a wet strength ofat least 1.4 grams per denier.

2. Artificial silk composed of filaments with an individual titre less than 1 denier, said silk having a dry strength of approximately 2.64 grams per demer, and a Wet strength of approximately 1.85 grams per denier.

In testimony whereof we afiix our signatures. r

AUGUST HARTMANN.

FRAN HOELKESKAMP. 

